Characterization of the structure of Y-Ba-Cu-O coated conductors

Author

Kung, H. ; Foltyn, S.R. ; Arendt, P.N. ; Maley, M.P.

Author_Institution

Div. of Mater. Sci. & Technol., Los Alamos Nat. Lab., NM, USA

Volume

9

Issue

2

fYear

1999

fDate

6/1/1999 12:00:00 AM

Firstpage

2034

Lastpage

2037

Abstract

Transmission electron microscopy (TEM) has been applied to the microstructural investigation of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) thick films deposited on polycrystalline Ni-based metal substrates by pulsed laser deposition. The films were found to be strongly textured with c-axis oriented grains aligned perpendicular to the substrates. Despite the large average in-plane misorientation (/spl theta//spl sim/14/spl deg/), as was estimated from selected area electron diffraction and X-ray diffraction, TEM inspection reveals colonies of submicron-sized grains with low angle (/spl theta//spl les/7/spl deg/) tilt grain boundaries. The linkage of the colony structures may provide a continuous percolation pathway for the supercurrent transport in YBCO, which may provide the mechanism for the higher than expected critical current density J/sub c/. Periodic arrays of grain boundary dislocations were observed, which may serve as effective flux pinners.

Keywords

X-ray diffraction; barium compounds; critical current density (superconductivity); dislocations; electron diffraction; flux pinning; grain boundaries; high-temperature superconductors; percolation; pulsed laser deposition; texture; thick films; transmission electron microscopy; yttrium compounds; SAED; TEM; X-ray diffraction; XRD; YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thick films; YBa/sub 2/Cu/sub 3/O/sub 7/; c-axis oriented grains; coated conductors; critical current density; effective flux pinners; film texture; grain boundary dislocations periodic arrays; in-plane misorientation; low angle tilt grain boundaries; microstructure; polycrystalline Ni-based metal substrates; pulsed laser deposition; selected area electron diffraction; structure; submicron-sized grain colonies; supercurrent continuous percolation pathway; transmission electron microscopy; Conductors; Grain boundaries; Inspection; Optical pulses; Pulsed laser deposition; Thick films; Transmission electron microscopy; X-ray diffraction; X-ray lasers; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.784864

Filename

784864